APPARATUS FOR PREPARING ICE CREAM AND LIKE FROZEN PRODUCTS

Abstract

The invention relates to an apparatus for making frozen yogurt sherbet and ice cream, comprising a heat transfer vessel and a scraper for use with a heat exchanger, wherein at least one heat exchanger vessel is used for rotation therein, said vessel comprising coupling means at its exterior bottom for coupling to a motor, a cooling medium within the housing surrounding the vessel, a motor for rotating the at least one vessel within the housing, and a scraper fixedly mounted on the housing extending into the vessel. The invention also relates to the vessel and scraper of the apparatus and to a method of preparing frozen yogurt sherbet and ice cream.

Claims

1-21. (canceled)

22. An apparatus for making frozen yogurt, sherbet and ice cream, comprising: a housing having a counter top with at least one aperture, at least one heat exchanger vessel positioned in said aperture for rotation therein, said at least one vessel comprising coupling means at its exterior bottom for coupling to a motor, the interior bottom of the vessel comprises adjacent curved U shaped troughs having a center peak between them, a cooling medium within the housing surrounding the vessel, a motor for rotating the at least one vessel within the housing, a single scraper blade fixedly mounted on the housing extending into the vessel, wherein the single scraper blade has a J shape with a straight vertical portion thereof extending into the vessel alongside its wall and the bottom portion of the single scraper blade curves and ends along the bottom of the vessel as the curvature of the bottom trough, and the straight vertical portion and the bottom curved portion of the scraper blade have different cross sections.

23. An apparatus as in claim 22, wherein the straight vertical portion has an irregular triangular cross section and said bottom curved portion has a right trapezoidal cross section.

24. An apparatus as in claim 23, wherein the right trapezoidal cross section of the bottom curved portion of the scraper blade has an acute angle of 38.

25. An apparatus as in claim 22, wherein the vessel comprises a cup having a lip and baffles or flanges around the outer wall of the cup to provide a large outer surface area for improved heat exchange.

26. An apparatus as in claim 22, wherein the vessel comprises a cup having a lip from which extends a wall, wherein the lower to of the wall has a thickness of 2 to 4 mm to improve heat exchange.

27. An apparatus as in claim 22, wherein the vessel comprises a removable liner.

28. An apparatus as in claim 22, wherein the scraper blade is made from stainless steel, copper zinc alloys, or engineering plastic.

29. An apparatus as in claim 22, wherein the scraper blade is made from engineering plastic.

30. An apparatus as in claim 22, comprising between 1 to 10 vessels with scrapers having capacities of to 2 liters.

31. An apparatus as in claim 22, comprising a home unit with 1 to 2 vessels.

32. A method of preparing yogurt, sherbet or ice cream, comprising: providing an apparatus as in claim 22, providing means to cool the vessel, cooling the outside of the vessel to a temperature between 10 C. and 30 C., to maintain an interior vessel temperature of about 5 C., introducing into the vessel the desired ingredients, activating the motor to rotate the vessel at a speed of between 20 and 300 rpm to cool, mix and aerate the contents of the vessel, and retrieving the freshly prepared yogurt, sherbet or ice cream from the vessel.

33. A method as in claim 32 wherein the product is retrieved from the vessel on a spoon, spatula or stick introduced into the vessel opposite the scraper blade, by catching the fresh yogurt, sherbet or ice cream as it builds up and removing same from the vessel while it is still rotating, to recover a thick layer of fresh yogurt, sherbet or ice cream with an overrun of 20-40%.

34. A method as in claim 32, wherein the product is retrieved after the rotation of the vessel has slowed down or stopped completely.

35. A scraper blade for use in an apparatus as claimed in claim 22, the blade having a J shape with a straight vertical portion and a bottom portion curve to conform to the bottom of a vessel as defined in claim 1, wherein the straight vertical portion has an irregular triangular cross section and said bottom curved portion has a right trapezoidal cross section.

36. A scraper as in claim 35, wherein the right trapezoidal cross section of the bottom curved portion of the scraper blade has an acute angle of 38.

37. An apparatus as in claim 29, wherein the engineering plastic comprises a metal insert to assure rigidity.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0048] FIG. 1 is illustrates a commercial ice cream vending apparatus in accordance with the present invention;

[0049] FIG. 2 is a to view of a counter top that is suitable for an ice cream vending machine as illustrated in FIG. 1;

[0050] FIG. 3 is a cross-sectional view of vessel and scraper in accordance with one embodiment of the present invention;

[0051] FIG. 4 illustrates an apparatus in accordance with one embodiment of the present invention;

[0052] FIG. 5 is a perspective cut view of another preferred embodiment of a vessel and scraper in accordance with the present invention;

[0053] FIG. 6 is a side view of a scraper blade in accordance with the present invention;

[0054] FIGS. 6A and 6B are cross-sectional views of the scraper blade of FIG. 6 along lines x-x and y-y respectively; and

[0055] FIGS. 7A and 7B illustrate perspective views of a scraper in accordance with a preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE DRAWINGS

[0056] Referring now to FIG. 1, there are shown an ice cream vending apparatus 10 with a counter top 12 and ice cream making apparatuses 14. Underneath the counter top there is a housing 16 containing one or more motors (not shown), to rotate the apparatuses, and circulating refrigeration facility to maintain a temperature of between 20 C. to 30 C. within the housing.

[0057] FIG. 2 shows a counter top 22 in which are contained eight ice cream making apparatuses. In the figure are seen vessels 24a-24h and scrapers 26a-26h. Trays 28a-28p can contain additions to the ice cream, such as fruits syrups, chocolate chips, etc.

[0058] FIG. 3 is a cross sectional view of a round vessel 30 and scraper 32, in accordance with one embodiment of the invention. The vessel 30 has a smooth inner wall and is open at the top with a circumferential lip 34 that supports the vessel 30 within an aperture of a counter top (not shown). The bottom interior of the vessel is rounded in the shape of two U's 36a and 36b that meet at a center peak 38. Baffles 37 or thin fins (not shown) surround the outer wall 39 to provide more surface area for heat exchange. A scraper 31 comprises a support section 33, for mounting on a counter top, and a scraper blade 35 having a curved bottom. The curved bottom of the blade is shaped to conform to the curve of the U shaped sections 36a, 36b. Coupling means, such as a socket 38a that can be quickly connected to a motor, such as by a bayonet, or snap fit connection, are provided at the exterior bottom of the vessel for coupling to a motor.

[0059] FIG. 4 illustrates an apparatus 40, in accordance with one embodiment of the invention. The apparatus 40 comprises a vessel 42 and scraper 44. The bottom 46 of the vessel 42 is connected to a motor 48 for rotation via a transmission belt system 49. An electric refrigeration system is utilized to maintain a temperature of between 20 C. to 30 C. within the housing to circulate and cool the vessel to the desired temperature.

[0060] The apparatus of this invention can be operated by portable energy such as battery.

[0061] FIG. 5 illustrates another embodiment of the present invention. There is shown a perspective cut view of a vessel and scraper 50. The vessel 52 has an upper lip 54 and smooth inner wall. The upper wall section 56 is relatively thick in order to give support to the vessel. The lower to of the wall 58 is very thin, in the order of 0.6 mm to 3.0 mm, preferably between 0.8 mm to 2 mm, and most preferably between 0.9 mm to 1.2 mm. This allows better heat exchange for cooling the section of the vessel where the ice cream is formed. The scraper is comprised of a shaft section 51 with a curved tip 53 that conforms to the U shaped trough that comprises the inner bottom 55 of the vessel 52. The scraper also has a handle 57 that is releasably attached by means of a devise 59 to a counter top (not shown).

[0062] FIG. 6 is a side view of a scraper 60 in accordance with this invention. The scraper 60 is shown with part of a handle 62 from which extends a straight blade 64 that terminates in a curved tip 66. The curved tip 66 is designed to conform to the curvature of a U shaped trough that forms half of a bottom of the vessel used to make ice cream according to the present invention. The straight blade has a cross-section, along line x-x, in the shape of an irregular triangle, as seen in FIG. 6A, and a different cross-section for the curved tip, along y-y, as seen in FIG. 6B. The slightly curved side 68 shown in FIG. 6A is the side of the blade that contacts the curved wall of a vessel, and preferably conforms to the same curvature.

[0063] In accordance with the present invention, an electric refrigeration unit is utilized to maintain a temperature of between 20 C. to 30 C. within the housing. In order to enable an optimal cooling, i.e., to maximize the cooling efficiency via conduction through the vessel content, the vessel wall is considerably thin, as stated earlier. A thin wall enables optimal cooling of the contents of the vessel with negligible energy loss.

[0064] The shaft of the scraper has at least one slightly curved side and is positioned adjacent to the slightly curved wall of the vessel leaving a small space between them, of approximately 0.1 mm, so that when the vessel rotates, the mass is scraped off the wall and pushed into the center peak where it is further turned and whipped.

[0065] The scraper can be made from rigid engineering plastic to assure rigidity and strength such as Delrin, as well as from metal, preferably from stainless steel such as ss304, which is acceptable for food processing. The blade may also be made of a first material and the handle of a second material. This may be useful when the need to replace parts arises.

[0066] Although the vessel may be constructed from many materials, including rigid plastics, it is preferred that the vessel be made of conducting material, such as bronze, copper alloys, aluminum, chrome-plated materials or stainless steel. Another possibility is to have the vessel lined with a thin metal, glass or plastic liner or cup fitted into the vessel in which the ice cream is made, which can easily be removed for cleaning or disposal.

[0067] The method for making ice cream, sherbet or yogurt with an apparatus of the invention as in FIG. 1, is as follows. The ingredients for preparing the desired end product are introduced into the vessel with the fixed scraper attached to the countertop. A refrigeration unit maintains a temperature of between 20 C. to 30 C. around the vessel, within the housing, while the interior vessel temperature is approximately 5 C. The ingredients may be either pre-mixed or introduced into the vessel separately, and can include powder mixes, liquid such as milk or water, and solid pieces such as fruits and nuts or flavor extract such as chocolate, vanilla etc. The motor 86 is then turned on and the vessel 10 rotated within the housing at approximately 50 to 300 rpm while the scraper is kept fixed. The ingredients are forced against the inner wall surface of the vessel by centrifugal force and the blade scrapes the mass off the wall of the vessel, mixing it with air and forcing it to the bottom and center of the vessel, where the mass is further churned and whipped with air. In commercial apparatuses that prepare individual portions, frozen yogurt or ice cream is prepared in about 2 to 3 minutes. The product is very fresh with a high overrun of 20% to 40%, and has a deliciously creamy texture and taste unobtainable from stored frozen yogurt or ice cream. The mixture may at first be only a powder, a liquid or a slurry but it becomes a creamy mass as a result of the whipping as the vessel rotates.

[0068] Industrial units can prepare larger portions in about 8 to 15 minutes. Very large batches may require somewhat more time, but are still very fast and of higher quality compared to other methods.

[0069] The method only requires atmospheric air to obtain a high overrun. If additional air is forced into the mixture, it is even possible to obtain an overrun of 100%.

[0070] By the term ice cream as used herein, is meant any ice cream, whether dairy, non-dairy or tofu. The use of the term ice cream also intends to include frozen yogurt and sherbet.

[0071] It will be appreciated by those skilled in the art that the invention is not limited to what has been shown and described hereinabove by way of example. Rather, the scope of the invention is defined solely by the claims which follow.